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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/rtc/rtc-nuc900.c
Initial import
Diffstat (limited to 'drivers/rtc/rtc-nuc900.c')
-rw-r--r--drivers/rtc/rtc-nuc900.c273
1 files changed, 273 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-nuc900.c b/drivers/rtc/rtc-nuc900.c
new file mode 100644
index 000000000..09fc1c19f
--- /dev/null
+++ b/drivers/rtc/rtc-nuc900.c
@@ -0,0 +1,273 @@
+/*
+ * Copyright (c) 2008-2009 Nuvoton technology corporation.
+ *
+ * Wan ZongShun <mcuos.com@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation;version 2 of the License.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/rtc.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/bcd.h>
+
+/* RTC Control Registers */
+#define REG_RTC_INIR 0x00
+#define REG_RTC_AER 0x04
+#define REG_RTC_FCR 0x08
+#define REG_RTC_TLR 0x0C
+#define REG_RTC_CLR 0x10
+#define REG_RTC_TSSR 0x14
+#define REG_RTC_DWR 0x18
+#define REG_RTC_TAR 0x1C
+#define REG_RTC_CAR 0x20
+#define REG_RTC_LIR 0x24
+#define REG_RTC_RIER 0x28
+#define REG_RTC_RIIR 0x2C
+#define REG_RTC_TTR 0x30
+
+#define RTCSET 0x01
+#define AERRWENB 0x10000
+#define INIRRESET 0xa5eb1357
+#define AERPOWERON 0xA965
+#define AERPOWEROFF 0x0000
+#define LEAPYEAR 0x0001
+#define TICKENB 0x80
+#define TICKINTENB 0x0002
+#define ALARMINTENB 0x0001
+#define MODE24 0x0001
+
+struct nuc900_rtc {
+ int irq_num;
+ void __iomem *rtc_reg;
+ struct rtc_device *rtcdev;
+};
+
+struct nuc900_bcd_time {
+ int bcd_sec;
+ int bcd_min;
+ int bcd_hour;
+ int bcd_mday;
+ int bcd_mon;
+ int bcd_year;
+};
+
+static irqreturn_t nuc900_rtc_interrupt(int irq, void *_rtc)
+{
+ struct nuc900_rtc *rtc = _rtc;
+ unsigned long events = 0, rtc_irq;
+
+ rtc_irq = __raw_readl(rtc->rtc_reg + REG_RTC_RIIR);
+
+ if (rtc_irq & ALARMINTENB) {
+ rtc_irq &= ~ALARMINTENB;
+ __raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
+ events |= RTC_AF | RTC_IRQF;
+ }
+
+ if (rtc_irq & TICKINTENB) {
+ rtc_irq &= ~TICKINTENB;
+ __raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
+ events |= RTC_UF | RTC_IRQF;
+ }
+
+ rtc_update_irq(rtc->rtcdev, 1, events);
+
+ return IRQ_HANDLED;
+}
+
+static int *check_rtc_access_enable(struct nuc900_rtc *nuc900_rtc)
+{
+ unsigned int timeout = 0x1000;
+ __raw_writel(INIRRESET, nuc900_rtc->rtc_reg + REG_RTC_INIR);
+
+ mdelay(10);
+
+ __raw_writel(AERPOWERON, nuc900_rtc->rtc_reg + REG_RTC_AER);
+
+ while (!(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_AER) & AERRWENB)
+ && timeout--)
+ mdelay(1);
+
+ if (!timeout)
+ return ERR_PTR(-EPERM);
+
+ return NULL;
+}
+
+static int nuc900_rtc_bcd2bin(unsigned int timereg,
+ unsigned int calreg, struct rtc_time *tm)
+{
+ tm->tm_mday = bcd2bin(calreg >> 0);
+ tm->tm_mon = bcd2bin(calreg >> 8);
+ tm->tm_year = bcd2bin(calreg >> 16) + 100;
+
+ tm->tm_sec = bcd2bin(timereg >> 0);
+ tm->tm_min = bcd2bin(timereg >> 8);
+ tm->tm_hour = bcd2bin(timereg >> 16);
+
+ return rtc_valid_tm(tm);
+}
+
+static void nuc900_rtc_bin2bcd(struct device *dev, struct rtc_time *settm,
+ struct nuc900_bcd_time *gettm)
+{
+ gettm->bcd_mday = bin2bcd(settm->tm_mday) << 0;
+ gettm->bcd_mon = bin2bcd(settm->tm_mon) << 8;
+
+ if (settm->tm_year < 100) {
+ dev_warn(dev, "The year will be between 1970-1999, right?\n");
+ gettm->bcd_year = bin2bcd(settm->tm_year) << 16;
+ } else {
+ gettm->bcd_year = bin2bcd(settm->tm_year - 100) << 16;
+ }
+
+ gettm->bcd_sec = bin2bcd(settm->tm_sec) << 0;
+ gettm->bcd_min = bin2bcd(settm->tm_min) << 8;
+ gettm->bcd_hour = bin2bcd(settm->tm_hour) << 16;
+}
+
+static int nuc900_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct nuc900_rtc *rtc = dev_get_drvdata(dev);
+
+ if (enabled)
+ __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)|
+ (ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
+ else
+ __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)&
+ (~ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
+
+ return 0;
+}
+
+static int nuc900_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct nuc900_rtc *rtc = dev_get_drvdata(dev);
+ unsigned int timeval, clrval;
+
+ timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TLR);
+ clrval = __raw_readl(rtc->rtc_reg + REG_RTC_CLR);
+
+ return nuc900_rtc_bcd2bin(timeval, clrval, tm);
+}
+
+static int nuc900_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct nuc900_rtc *rtc = dev_get_drvdata(dev);
+ struct nuc900_bcd_time gettm;
+ unsigned long val;
+ int *err;
+
+ nuc900_rtc_bin2bcd(dev, tm, &gettm);
+
+ err = check_rtc_access_enable(rtc);
+ if (IS_ERR(err))
+ return PTR_ERR(err);
+
+ val = gettm.bcd_mday | gettm.bcd_mon | gettm.bcd_year;
+ __raw_writel(val, rtc->rtc_reg + REG_RTC_CLR);
+
+ val = gettm.bcd_sec | gettm.bcd_min | gettm.bcd_hour;
+ __raw_writel(val, rtc->rtc_reg + REG_RTC_TLR);
+
+ return 0;
+}
+
+static int nuc900_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct nuc900_rtc *rtc = dev_get_drvdata(dev);
+ unsigned int timeval, carval;
+
+ timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TAR);
+ carval = __raw_readl(rtc->rtc_reg + REG_RTC_CAR);
+
+ return nuc900_rtc_bcd2bin(timeval, carval, &alrm->time);
+}
+
+static int nuc900_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct nuc900_rtc *rtc = dev_get_drvdata(dev);
+ struct nuc900_bcd_time tm;
+ unsigned long val;
+ int *err;
+
+ nuc900_rtc_bin2bcd(dev, &alrm->time, &tm);
+
+ err = check_rtc_access_enable(rtc);
+ if (IS_ERR(err))
+ return PTR_ERR(err);
+
+ val = tm.bcd_mday | tm.bcd_mon | tm.bcd_year;
+ __raw_writel(val, rtc->rtc_reg + REG_RTC_CAR);
+
+ val = tm.bcd_sec | tm.bcd_min | tm.bcd_hour;
+ __raw_writel(val, rtc->rtc_reg + REG_RTC_TAR);
+
+ return 0;
+}
+
+static struct rtc_class_ops nuc900_rtc_ops = {
+ .read_time = nuc900_rtc_read_time,
+ .set_time = nuc900_rtc_set_time,
+ .read_alarm = nuc900_rtc_read_alarm,
+ .set_alarm = nuc900_rtc_set_alarm,
+ .alarm_irq_enable = nuc900_alarm_irq_enable,
+};
+
+static int __init nuc900_rtc_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct nuc900_rtc *nuc900_rtc;
+
+ nuc900_rtc = devm_kzalloc(&pdev->dev, sizeof(struct nuc900_rtc),
+ GFP_KERNEL);
+ if (!nuc900_rtc)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ nuc900_rtc->rtc_reg = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(nuc900_rtc->rtc_reg))
+ return PTR_ERR(nuc900_rtc->rtc_reg);
+
+ platform_set_drvdata(pdev, nuc900_rtc);
+
+ nuc900_rtc->rtcdev = devm_rtc_device_register(&pdev->dev, pdev->name,
+ &nuc900_rtc_ops, THIS_MODULE);
+ if (IS_ERR(nuc900_rtc->rtcdev)) {
+ dev_err(&pdev->dev, "rtc device register failed\n");
+ return PTR_ERR(nuc900_rtc->rtcdev);
+ }
+
+ __raw_writel(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_TSSR) | MODE24,
+ nuc900_rtc->rtc_reg + REG_RTC_TSSR);
+
+ nuc900_rtc->irq_num = platform_get_irq(pdev, 0);
+ if (devm_request_irq(&pdev->dev, nuc900_rtc->irq_num,
+ nuc900_rtc_interrupt, 0, "nuc900rtc", nuc900_rtc)) {
+ dev_err(&pdev->dev, "NUC900 RTC request irq failed\n");
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+static struct platform_driver nuc900_rtc_driver = {
+ .driver = {
+ .name = "nuc900-rtc",
+ },
+};
+
+module_platform_driver_probe(nuc900_rtc_driver, nuc900_rtc_probe);
+
+MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
+MODULE_DESCRIPTION("nuc910/nuc920 RTC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:nuc900-rtc");